The present invention relates to inhibiting the passage of moisture between a face mask and a wearer""s face.
Face masks serve many purposes including protecting the wearer from environmental contaminants and protecting those with whom the wearer comes into contact from the wearer""s exhaled breath. It is often desirable to wear eyewear such as glasses, safety goggles, and face shields in conjunction with a face mask to obtain additional protection. Unfortunately, warm, moist air escaping from the face mask tends to condense on eyewear causing fogging and, consequently, impairing visibility.
In one aspect, the invention features a face mask that includes a mask portion, a resilient member, and an adhesive portion. The resilient member and the adhesive portion are alternately positionable against the wearer (e.g., between the mask portion and the wearer), preferably to inhibit the flow of vapor between the mask and the wearer. The resilient member and the adhesive portion are also alternately positionable against the wearer to inhibit the flow of vapor between the positioned resilient member or adhesive portion and the wearer.
The resilient member is preferably foldable such that, when folded, the resilient member is positionable between the mask portion and the wearer. In one embodiment, the resilient member is foldable onto the mask portion. The resilient member can also be folded onto itself. In other embodiments, when the resilient member is folded, the adhesive portion is disposed between the resilient member and the mask portion. In some embodiments, the resilient member overlies the adhesive portion. When folded, the resilient member has a propensity to unfold.
In one embodiment, the resilient member includes a resilient exterior surface and an interior surface, and the adhesive portion is disposed on the interior surface of the resilient member. The mask can further include a second adhesive portion disposed on the resilient exterior surface of the resilient member. In other embodiments, the adhesive portion is disposed on the interior face-contacting surface of the mask portion.
The mask portion includes a major exterior mask surface, a major interior face-contacting surface, and an edge common to the interior and exterior mask surfaces. In one embodiment, the resilient member is affixed to the exterior mask surface and is dimensioned to be foldable over the common edge such that, when folded, the major interior surface of the resilient member is positionable against the wearer.
In preferred embodiments, the resilient member includes compacted higher density regions and pillowed lower density regions. The pillowed lower density regions are preferably displaced to one side of a plane defined by the base of the compacted higher density regions. The resilient member includes a matrix that includes the pillowed lower density regions and the compacted higher density regions. The compacted higher density regions preferably form a tortuous path.
One example of a useful resilient member is a nonwoven web that includes pressure sensitive adhesive microfibers.
The face mask can further include a variety of other components including a conformable strip (e.g., a conformable metal). The conformable strip can be disposed on the resilient member or affixed to the mask portion. The face mask can also include a release liner overlying the adhesive portion. In some embodiments, the resilient member is disposed on the release liner and is removable from the mask with the release liner to expose the adhesive portion.
In one embodiment, the face mask includes a filter, a resilient member of pillowed lower density regions and compacted higher density regions affixed to the filter, and an adhesive portion disposed on the resilient member.
In a second aspect, the invention features a face mask that includes a mask portion and a pillowed web affixed to the mask portion. The pillowed web includes a plurality of pillowed lower density regions and compacted higher density regions.
In a third aspect, the invention features a method for using the above-described face mask. The method includes selecting one of either the resilient member or the adhesive portion, and contacting a wearer with the selected resilient member or adhesive portion to form a seal between the mask and the wearer. Preferably the contacting forms a vapor barrier to inhibit the passage of moisture between the mask and the wearer.
The face mask provides a wearer with a choice between two alternate mechanisms for preventing the fogging of the wearer""s eyewear in a single mask.
Other features and advantages of the invention will become apparent from the following description of the preferred embodiments thereof, and from the claims.